FFmpeg
Data Structures | Macros | Functions | Variables
vf_readeia608.c File Reference

Filter for reading closed captioning data (EIA-608). More...

#include <string.h>
#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "libavutil/timestamp.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"

Go to the source code of this file.

Data Structures

struct  ReadEIA608Context
 

Macros

#define FALL   0
 
#define RISE   1
 
#define OFFSET(x)   offsetof(ReadEIA608Context, x)
 
#define FLAGS   AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
 

Functions

 AVFILTER_DEFINE_CLASS (readeia608)
 
static int query_formats (AVFilterContext *ctx)
 
static int config_input (AVFilterLink *inlink)
 
static void extract_line (AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *in, int line)
 
static int filter_frame (AVFilterLink *inlink, AVFrame *in)
 
static av_cold void uninit (AVFilterContext *ctx)
 

Variables

static const AVOption readeia608_options []
 
static const AVFilterPad readeia608_inputs []
 
static const AVFilterPad readeia608_outputs []
 
AVFilter ff_vf_readeia608
 

Detailed Description

Filter for reading closed captioning data (EIA-608).

See also https://en.wikipedia.org/wiki/EIA-608

Definition in file vf_readeia608.c.

Macro Definition Documentation

#define FALL   0

Definition at line 39 of file vf_readeia608.c.

Referenced by extract_line().

#define RISE   1

Definition at line 40 of file vf_readeia608.c.

Referenced by extract_line().

#define OFFSET (   x)    offsetof(ReadEIA608Context, x)

Definition at line 58 of file vf_readeia608.c.

Definition at line 59 of file vf_readeia608.c.

Function Documentation

AVFILTER_DEFINE_CLASS ( readeia608  )
static int query_formats ( AVFilterContext ctx)
static

Definition at line 79 of file vf_readeia608.c.

static int config_input ( AVFilterLink inlink)
static

Definition at line 97 of file vf_readeia608.c.

static void extract_line ( AVFilterContext ctx,
AVFilterLink inlink,
AVFrame in,
int  line 
)
static

Definition at line 127 of file vf_readeia608.c.

Referenced by filter_frame().

static int filter_frame ( AVFilterLink inlink,
AVFrame in 
)
static

Definition at line 260 of file vf_readeia608.c.

static av_cold void uninit ( AVFilterContext ctx)
static

Definition at line 274 of file vf_readeia608.c.

Variable Documentation

const AVOption readeia608_options[]
static
Initial value:
= {
{ "scan_min", "set from which line to scan for codes", OFFSET(start), AV_OPT_TYPE_INT, {.i64=0}, 0, INT_MAX, FLAGS },
{ "scan_max", "set to which line to scan for codes", OFFSET(end), AV_OPT_TYPE_INT, {.i64=29}, 0, INT_MAX, FLAGS },
{ "mac", "set minimal acceptable amplitude change for sync codes detection", OFFSET(mac), AV_OPT_TYPE_FLOAT, {.dbl=.2}, 0.001, 1, FLAGS },
{ "spw", "set ratio of width reserved for sync code detection", OFFSET(spw), AV_OPT_TYPE_FLOAT, {.dbl=.27}, 0.1, 0.7, FLAGS },
{ "mhd", "set max peaks height difference for sync code detection", OFFSET(mhd), AV_OPT_TYPE_FLOAT, {.dbl=.1}, 0, 0.5, FLAGS },
{ "mpd", "set max peaks period difference for sync code detection", OFFSET(mpd), AV_OPT_TYPE_FLOAT, {.dbl=.1}, 0, 0.5, FLAGS },
{ "msd", "set first two max start code bits differences", OFFSET(msd), AV_OPT_TYPE_FLOAT, {.dbl=.02}, 0, 0.5, FLAGS },
{ "bhd", "set min ratio of bits height compared to 3rd start code bit", OFFSET(bhd), AV_OPT_TYPE_FLOAT, {.dbl=.75}, 0.01, 1, FLAGS },
{ "th_w", "set white color threshold", OFFSET(wth), AV_OPT_TYPE_FLOAT, {.dbl=.35}, 0.1, 1, FLAGS },
{ "th_b", "set black color threshold", OFFSET(bth), AV_OPT_TYPE_FLOAT, {.dbl=.15}, 0, 0.5, FLAGS },
{ "chp", "check and apply parity bit", OFFSET(chp), AV_OPT_TYPE_BOOL, {.i64= 0}, 0, 1, FLAGS },
{ "lp", "lowpass line prior to processing", OFFSET(lp), AV_OPT_TYPE_BOOL, {.i64= 0}, 0, 1, FLAGS },
{ NULL }
}
#define NULL
Definition: coverity.c:32
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
#define FLAGS
Definition: vf_readeia608.c:59
void INT64 start
Definition: avisynth_c.h:766
#define OFFSET(x)
Definition: vf_readeia608.c:58

Definition at line 61 of file vf_readeia608.c.

const AVFilterPad readeia608_inputs[]
static
Initial value:
= {
{
.name = "default",
.filter_frame = filter_frame,
.config_props = config_input,
},
{ NULL }
}
#define NULL
Definition: coverity.c:32
static int config_input(AVFilterLink *inlink)
Definition: vf_readeia608.c:97
static int filter_frame(AVFilterLink *inlink, AVFrame *in)

Definition at line 281 of file vf_readeia608.c.

const AVFilterPad readeia608_outputs[]
static
Initial value:
= {
{
.name = "default",
},
{ NULL }
}
#define NULL
Definition: coverity.c:32

Definition at line 291 of file vf_readeia608.c.

AVFilter ff_vf_readeia608
Initial value:
= {
.name = "readeia608",
.description = NULL_IF_CONFIG_SMALL("Read EIA-608 Closed Caption codes from input video and write them to frame metadata."),
.priv_size = sizeof(ReadEIA608Context),
.priv_class = &readeia608_class,
}
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:125
static av_cold void uninit(AVFilterContext *ctx)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
static const AVFilterPad readeia608_outputs[]
static const AVFilterPad readeia608_inputs[]
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int query_formats(AVFilterContext *ctx)
Definition: vf_readeia608.c:79

Definition at line 299 of file vf_readeia608.c.